Specifically I'm asking about Lair Assault: Kill the Wizard, but would also like to know if this is an overall rule for Lair Assaults. It's my first Lair Assault and I want to build my potential PCs as optimized as I possibly can within the confines of the Lair Assault rules. I know long and short rests are prohibited, but I am specifically trying to figure out if I should be picking encounter powers or dailies for utilities and also whether or not I should weigh encounter powers that have "until the end of the encounter" effects as being more optimized/powerful.

Kill the Wizard actually restricted characters to being either Drow or Revenant, for storyline reasons. This was the only exception in the series, with every other installment being all-inclusive.
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Raymond MartineauSep 26 '14 at 18:59